CN107979105B

CN107979105B - Intelligent phase electricity output exchange device and control method thereof

Info

Publication number: CN107979105B
Application number: CN201610922612.5A
Authority: CN
Inventors: 谢楠; 张海波
Original assignee: Zhejiang University of Water Resources and Electric Power
Current assignee: Zhejiang University of Water Resources and Electric Power
Priority date: 2016-10-24
Filing date: 2016-10-24
Publication date: 2021-05-04
Anticipated expiration: 2036-10-24
Also published as: CN107979105A

Abstract

The invention discloses an intelligent phase electricity output exchange device and a control method thereof. The system comprises an A phase, a B phase, a C phase, a zero line N, three load interfaces, a controller, a plurality of nodes, a three-phase power factor monitor, an interface power factor monitor, two phase voltage sampling circuits, two single-phase inverter power supplies, two filters, two isolation transformers, two load interface voltage sampling circuits and a plurality of switches, wherein the three-phase power factor monitor, the interface power factor monitor, the two phase voltage sampling circuits, the two single-phase inverter power supplies, the two filters, the two isolation transformers, the two load interface voltage sampling circuits and the plurality of switches are respectively connected with the controller; the change of input phase electricity among all load interfaces is realized through the control of the controller.

Description

Intelligent phase electricity output exchange device and control method thereof

Technical Field

The invention relates to the technical field of phase electricity selection of three-phase four-wire power outlets, in particular to an intelligent phase electricity output exchange device and a control method thereof.

Background

With the development of economic society, the types of electric equipment are more and more. Because the existing power supply system is generally a three-phase power supply system, in the three-phase power supply system, if the power factors on the three phases are largely asymmetric, unbalanced operation of a power grid occurs, and power grid jitter occurs.

When the power grid operates in an unbalanced state, a transformer in the power grid is in an asymmetric operation state, zero sequence current of the transformer is overlarge due to the transformer in the asymmetric operation state, the temperature of local parts of the transformer is increased due to the overlarge zero sequence current, and the transformer can be burnt if the temperature of the local parts of the transformer is overlarge, so that a power failure accident of a power supply system is caused.

When the grid is operating in an unbalanced manner, if it is desired to change the unbalanced network to a balanced network, it is currently the practice to manually switch a portion of the loads on the high power phase line of one large scale segment to the low power phase line of another large scale segment. Because the switching mode has more loads switched instantly, the impact current switched instantly is overlarge, the switching equipment can be burnt by the overlarge impact current, and the load can be disordered or even damaged due to different power supply phase lines before and after the load is switched at the moment of switching the load.

Disclosure of Invention

The invention aims to solve the defect that the power supply phase of a load interface of the existing three-phase four-wire power supply is not easy to change, and provides an intelligent phase power output switching device and a control method thereof, wherein the intelligent phase power output switching device can enable the power supply phase of the load interface of the three-phase four-wire power supply to be easy to change, can automatically switch the power supply phase of the load interface according to the unbalance of power factors on three phases, has high safety and good reliability, can intelligently and automatically detect the self switching fault of a compound switch, can switch the compound switch at the accurate time point of the current zero crossing point, and has high.

In order to achieve the purpose, the invention adopts the following technical scheme:

the intelligent phase electric output switching device comprises an A phase, a B phase, a C phase, a zero line N, A wiring port, a B wiring port, a C wiring port, a first load interface, a second load interface, a third load interface, a controller, a node J1, a node J2, a node J3, a node J4, a node J5, a node J6, a node J7 and a node J8;

the power factor monitoring device further comprises a three-phase power factor monitor, a phase voltage sampling circuit, a single-phase inverter power supply, a filter, an isolation transformer, a load interface voltage sampling circuit, an interface power factor monitor, a phase voltage sampling circuit, a single-phase inverter power supply, a filter, an isolation transformer, a load interface voltage sampling circuit, a switch K1, a switch K2, a switch K3, a switch K4, a switch K5, a switch K6, a switch K7, a switch K8, a switch K9, a switch K10, a switch K11, a switch K12, a switch K13, a switch K14, a switch K15, a switch K16, a switch K17, a switch K18, a switch K19, a switch K20 and a switch K21 which are respectively connected with the controller;

the phase A is connected to the live wire input end of the phase A wiring port, the phase B is connected to the live wire input end of the phase B wiring port, the phase C is connected to the live wire input end of the phase C wiring port, and the zero line input end of the phase A wiring port, the zero line input end of the phase B wiring port and the zero line input end of the phase C wiring port are all connected with a zero line N;

one end of the switch K19, a monitoring end a of the three-phase power factor monitor, a sampling end a of the first-phase voltage sampling circuit, a sampling end a of the second-phase voltage sampling circuit, one end of the switch K1, the output end of the A wiring port, one end of the switch K9, one end of the switch K13 and one end of the switch K15 are respectively connected with a node J1;

one end of the switch K20, a B monitoring end of the three-phase power factor monitor, a B sampling end of the first-phase voltage sampling circuit, a B sampling end of the second-phase voltage sampling circuit, one end of the switch K2, an output end of the B wiring port, one end of the switch K8, one end of the switch K12 and one end of the switch K14 are respectively connected with a node J2;

one end of the switch K21, a C monitoring end of the three-phase power factor monitor, a C sampling end of the first-phase voltage sampling circuit, a C sampling end of the second-phase voltage sampling circuit, one end of the switch K3, an output end of the C wiring port, one end of the switch K7, one end of the switch K10 and one end of the switch K11 are respectively connected with a node J3;

the power output end of the first isolation transformer, the sampling end of the first load interface voltage sampling circuit, one end of the switch K4, one end of the switch K5 and one end of the switch K6 are respectively connected with a node J4;

the power output end of the second isolation transformer, the sampling end of the second load interface voltage sampling circuit, one end of the switch K16, one end of the switch K17 and one end of the switch K18 are respectively connected with a node J5;

the other end of the switch K4, the other end of the switch K9, the other end of the switch K10, the other end of the switch K14, the other end of the switch K16, a first monitoring end of the interface power factor monitor and a first load interface are respectively connected with a node J6;

the other end of the switch K5, the other end of the switch K8, the other end of the switch K11, the other end of the switch K15, the other end of the switch K17, a second monitoring end of the interface power factor monitor and a second load interface are respectively connected with a node J7;

the other end of the switch K6, the other end of the switch K7, the other end of the switch K12, the other end of the switch K13, the other end of the switch K18, the third monitoring end of the interface power factor monitor and the third load interface are respectively connected with a node J8;

the other end of the switch K1, the other end of the switch K2 and the other end of the switch K3 are all connected with the power supply input end of a first single-phase inverter power supply, the input end of a first filter is connected with the power supply output end of the first single-phase inverter power supply, and the output end of the first filter is connected with the power supply input end of a first isolation transformer;

the other end of the switch K19, the other end of the switch K20 and the other end of the switch K21 are all connected with the power supply input end of a second single-phase inverter, the input end of a second filter is connected with the power supply output end of the second single-phase inverter, and the output end of the second filter is connected with the power supply input end of a second isolation transformer;

the switch K1, the switch K2, the switch K3, the switch K7, the switch K8, the switch K9, the switch K10, the switch K11, the switch K12, the switch K13, the switch K14, the switch K15, the switch K19, the switch K20 and the switch K21 are all composite switches with completely identical circuit structures;

the combination switch comprises a first node, a second node, a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch and a node M_aNode M_bNode M_cNode M_dNode M_eInductor L_aCapacitor C_aCapacitor C₀Capacitor C₂Diode D₁Diode D₂Diode D₃Diode D₄Photoelectric coupler OPT and resistor R₀Resistance R₁Resistance R₂And a change-over switch K_aThe controller comprises a pulse counter; change-over switch K_aComprising a thyristor switch K_bAnd magnetic latching relay switch K_cThe photo coupler OPT comprises a light emitting diode D₅And a photo transistor Q₀(ii) a Silicon controlled switch K_bAnd a magnetically held relay switch K_cOne end of the first and second switches is respectively connected with a first node, and the thyristor switch K_bThe other end of the first switch, one end of the third switch, one end of the fourth switch and the inductor L_aOne end of each is connected with the node M_aConnection, inductance L_aAnother terminal of (1), a capacitor C_aOne end of the first switch, one end of the second switch, one end of the fifth switch and one end of the sixth switch are respectively connected with the node M_bConnecting, magnetic latching relay switch K_cThe other end of the first switch and the other end of the second switch are respectively connected with a node M_cConnection, capacitance C₂One end of the fourth switch, the other end of the fourth switch and a diode D₁Positive terminal of (2) and diode D₃Respectively with the node M_dConnected, diode D₂Anode terminal of (1), diode D₄Negative terminal of (1), capacitor C₀And a resistor R₂One end of each is connected with the node M_eThe other end of the third switch is connected with one end of a resistor R1, and the other end of a resistor R1 is connected with a capacitor C₂The other end of the fifth switch is connected with a capacitor C₀The other end of the sixth switch is connected with a resistor R₂Is connected at the other end to a capacitor C_aThe other end of the diode D is connected to a second node₁And diode D₂Are respectively connected with the light emitting diode D₅On the positive terminal of a diode D₃Positive terminal of (2) and diode D₄Are respectively connected with the positive terminals of the light emitting diodes D₅On the negative terminal of the triode, a phototriode Q₀Respectively with the resistor R₀Is connected with a controller, a phototriode Q₀The emitter of the power supply module is connected with a signal grounding end SGND, and the self-powered power supply module is respectively connected with a resistor R₀The other end of the silicon-based switch, the magnetic drive circuit, the silicon drive circuit and the controller are connected, and the silicon drive circuit is respectively connected with the silicon controlled switch K_bIs connected with the controller, and the magnetic drive circuit is respectively connected with a magnetic latching relay switch K_cThe control end of the controller is connected with the controller;

in the same time section, the first node can only be in conductive connection with one of the three phases of A phase, B phase and C phase; and the second node is connected to the zero line N.

This scheme enables the load interface power supply looks of three-phase four-wire power and easily changes to can go up the unbalanced automatic exchange of load interface power supply looks according to the three-phase, safe and reliable, intelligent degree is high.

Preferably, the first load interface is a quick connector, the quick connector comprises a plug and a shell, an insulating tube is fixedly arranged on the upper surface of the shell upwards, a pressure sensor connected with a controller is arranged on the outer tube wall of the insulating tube, a through hole communicated with the inner cavity of the shell is fixedly arranged on the upper surface of the shell surrounded by the insulating tube, a contact pin is fixedly arranged in the through hole, the lower end of the contact pin is positioned in the inner cavity of the shell, and the upper end of the contact pin is positioned in the insulating tube; two ends of one lead are respectively connected with the lower end of the contact pin and the joint J6 in a conductive manner; the plug comprises an insulating insertion tube and a conductive tube arranged in the insulating insertion tube; the inner diameter of the insulating insertion tube is matched with the outer diameter of the insulating tube, and the diameter of the contact pin is matched with the inner diameter of the conductive tube; the structure of the second load interface and the structure of the third load interface are completely the same as the structure of the first load interface; the top end of the contact pin is provided with a conical tip.

Preferably, the wireless communication device further comprises a memory, a wireless module, an address encoder and a server which are respectively connected with the controller.

A control method suitable for the electric output switching unit of intellectual phase, the control method includes the zero passage switching control process of the compound switch, when regard compound switch as the zero passage switching switch to use, the zero passage switching control process of the compound switch is as follows:

(4-1) putting a compound switch;

(4-1-1) when the compound switch is to be put into the C phase, the voltage U on the C phase is detected_CNExact point in time at zero crossing, when voltage U_CNWhen the zero crossing point is reached, the controller immediately turns to the silicon controlled switch K_bSending out a conduction control signal, and switching on or off the thyristor_bThen conducting;

(4-1-2) when the thyristor switch K_bAfter the set time of conduction, the current I is detected₁Exact point in time at zero crossing, when current I₁When the zero crossing point is reached, the controller immediately keeps the relay switch K towards the magnetism_cSending out a closing control signal to magnetically hold a relay switch K_cClosing immediately;

(4-1-3) then the current I is detected again₁Exact point in time at zero crossing, when current I₁When the zero crossing point is reached, the controller immediately turns to the silicon controlled switch K_bSending out turn-off control signal, silicon controlled switch K_bThen is turned off, and the relay switch K is only kept by magnetism_cKeeping the power supply loop working, and completing the input work of the compound switch to the C phase;

(4-2) cutting off the combination switch;

(4-2-1) when the compound switch on the C phase is to be cut off, the current I is detected first₁Exact point in time at zero crossing, when current I₁When the zero crossing point is reached, the controller immediately turns to the silicon controlled switch K_bSending out a conduction control signal, and switching on or off the thyristor_bThen turned on immediately, and the thyristor switch K is delayed for a period of time_bReliable conduction;

(4-2-2) in the thyristor switch K_bWhen turned on, the current I is detected again₁Exact point in time at zero crossing, when current I₁When the zero crossing point is reached, the controller immediately keeps the relay switch K towards the magnetism_cSends out a turn-off control signal to magnetically hold a relay switch K_cThen the circuit is disconnected;

(4-2-3) then the current I is detected again₁Exact point in time at zero crossing, when current I₁When the zero crossing point is reached, the controller immediately turns to the silicon controlled switch K_bSending out turn-off control signal, silicon controlled switch K_bThen the power is cut off; the combination switch has now been completely cut from phase C.

A control method suitable for an intelligent phase power output exchange device comprises a load interface power supply phase automatic exchange process, wherein the load interface power supply phase automatic exchange process comprises the following steps:

(5-2) the three-phase power factor monitor respectively carries out power factor balance monitoring on the A phase, the B phase and the C phase within a set time interval, monitoring data of each phase are respectively uploaded to the controller, and the controller immediately calculates and processes the monitoring data uploaded by the three-phase power factor monitor;

if the controller calculates and processes the monitoring data uploaded by the three-phase power factor monitor to obtain the phase with the maximum current power factor as the A phase, the phase with the minimum current power factor as the C phase and the active power factor P at the moment_ACGreater than a set value P₀When the temperature of the water is higher than the set temperature,determining which of the three phases, namely, the phase A, the phase B and the phase C, is currently supplying power to the first load interface, the second load interface and the third load interface;

(5-3) the controller immediately sends an interface monitoring instruction to the interface power factor monitor, the interface power factor monitor immediately monitors power factors on the first load interface, the second load interface and the third load interface simultaneously, monitoring data on the first load interface, the second load interface and the third load interface are respectively uploaded to the controller, and the controller immediately calculates and processes the monitoring data uploaded by the interface power factor monitor;

when the controller calculates and processes monitoring data uploaded by the interface power factor monitor, a first load interface, a second load interface and a third load interface can be respectively determined according to which of the three phases of A, B and C supplies power to the first load interface, the second load interface and the third load interface;

if it is determined that the power supply phase on the first load interface is supplied by the phase A, the power supply phase on the second load interface is supplied by the phase B, and the power supply phase on the third load interface is supplied by the phase C, then the switch K7, the switch K8 and the switch K9 are all in a closed state, the switch K1, the switch K2, the switch K3, the switch K4, the switch K5, the switch K6, the switch K10, the switch K11, the switch K12, the switch K13, the switch K14, the switch K15, the switch K16, the switch K17 and the switch K18 are all in an open state, the sampling switch blade of the first-phase voltage sampling circuit is located at the end d, and the sampling switch blade of the second-phase voltage sampling circuit is located at the end d;

(5-4) making the absolute value of the difference between the absolute values of the power factors on the A phase, the B phase and the C phase smaller than a set value P₀If the power supply phase on the first load interface is changed from the phase A to the phase C, the power supply phase on the second load interface is still supplied from the phase B, and the power supply phase on the third load interface is changed from the phase C to the phase A;

(5-5) the automatic exchange process of the power supply phase on the first load interface from the A-phase power supply to the C-phase power supply and the power supply phase on the third load interface from the C-phase power supply to the A-phase power supply is as follows:

(5-5-1) firstly, connecting a sampling knife switch of a first phase voltage sampling circuit to a sampling end a of the first phase voltage sampling circuit to be communicated with the phase A, and collecting a voltage signal of the phase A by the first phase voltage sampling circuit and uploading the voltage signal to a controller;

then, a switch K1 is closed to enable the first single-phase inverter power supply to be connected with the phase A; under the control of the controller, a voltage signal output by the first single-phase inverter power supply takes an A-phase voltage signal as a reference, and a voltage signal output by the first single-phase inverter power supply as a feedback signal to form first closed-loop control, a first driving signal is generated in the controller, so that a first voltage waveform output by the first single-phase inverter power supply is filtered by a first filter and then is output by a first isolation transformer to form a stable first sine wave power supply, and the first sine wave power supply output by the first isolation transformer and the A-phase voltage have the same amplitude and the same phase under the control of the controller;

the FORMTEXT opens the switch K9, and the state of the power supply phase on the first load interface is the same as that of the power supply phase on the a phase;

then, the switch K1 is still closed, the sampling knife switch of the first phase voltage sampling circuit is connected to the C sampling end of the first phase voltage sampling circuit to be communicated with the C phase, and the first phase voltage sampling circuit collects the voltage signal of the C phase and uploads the voltage signal to the controller; the controller adopts phase shift control, so that a voltage signal output by a first single-phase inverter power supply takes a voltage signal of a C phase as a reference, and a voltage signal output by the first single-phase inverter power supply as a feedback signal to form new first closed-loop control;

(5-5-2) similarly, connecting a sampling knife switch of the second-phase voltage sampling circuit to a C sampling end of the second-phase voltage sampling circuit to be communicated with the C phase, and collecting the voltage signal of the C phase by the second-phase voltage sampling circuit and uploading the voltage signal to the controller;

then, a switch K21 is closed to enable the second single-phase inverter power supply to be connected with the C; under the control of the controller, the voltage signal output by the second single-phase inverter power supply takes the voltage signal of the C phase as a reference, and the voltage signal output by the second single-phase inverter power supply as a feedback signal to form second closed-loop control, a second driving signal is generated in the controller, so that the second voltage waveform output by the second single-phase inverter power supply is filtered by a second filter and then is output by a second isolation transformer to form a stable second sine wave power supply, and the second sine wave power supply output by the second isolation transformer and the C phase voltage have the same amplitude and the same phase under the control of the controller;

then, the switch K18 and the switch K7 are closed at the same time, and the state of the power supply phase on the third load interface is the same as that of the power supply phase on the C phase;

then, the switch K21 is still closed, the sampling knife switch of the second phase voltage sampling circuit is connected to the a sampling end of the second phase voltage sampling circuit to be communicated with the phase A, and the second phase voltage sampling circuit collects the voltage signal of the phase A and uploads the voltage signal to the controller; the controller adopts phase shift control to enable a voltage signal output by the second single-phase inverter power supply to take an A-phase voltage signal as a reference and take a voltage signal output by the second single-phase inverter power supply as a feedback signal to form new second closed-loop control, a second driving signal of SPWM is generated in the controller, a second voltage waveform output by the second single-phase inverter power supply is filtered by a second filter and then is output by a second isolation transformer to form a stable second sine wave power supply, the second sine wave power supply output by the second isolation transformer and the A-phase voltage have the same amplitude and the same phase under the control of the controller, and the state of a power supply phase on a third load interface is the same as the state of a power supply phase on the A-phase;

(5-5-3) then, simultaneously closing the switch K10, the disconnecting switch K4, the closing switch K13 and the disconnecting switch K18, wherein the power supply phase on the first load interface is completely supplied with power by the C phase, and the power supply phase on the third load interface is completely supplied with power by the A phase;

(5-5-4) finally, rotating the sampling knife switch of the first phase voltage sampling circuit to the d end, rotating the sampling knife switch of the second phase voltage sampling circuit to the d end, and disconnecting the switch K1 and the switch K21, so that the first phase voltage sampling circuit, the first single-phase inverter power supply, the first filter, the first isolation transformer, the second phase voltage sampling circuit, the second single-phase inverter power supply, the second filter and the second isolation transformer all exit from the load interface to supply the operation of automatic phase switching;

(5-5-5) at this point, the automatic exchange process of the load interface power supply phase for changing the power supply phase on the first load interface from the A-phase power supply to the C-phase power supply and changing the power supply phase on the third load interface from the C-phase power supply to the A-phase power supply is finished;

(5-5-6) similarly, the principle of exchanging the power supply phase on the first load interface, the power supply phase on the second load interface and the power supply phase on the third load interface is the same as the principle of changing the power supply phase on the first load interface from the A-phase power supply to the C-phase power supply and changing the power supply phase on the third load interface from the C-phase power supply to the A-phase power supply.

If two intelligent phase electric output switching devices are provided, the two intelligent phase electric output switching devices can be in mutual wireless signal connection with each other through respective wireless modules;

when only one of the three load interfaces in the first intelligent phase electric output switching device is connected with a load, and only two of the three load interfaces in the second intelligent phase electric output switching device are connected with loads;

and if the load interface of the first intelligent phase electric output exchange device is determined to be supplied with power by the phase A, enabling the two load interfaces of the second intelligent phase electric output exchange device to be supplied with power by the phase B and the phase C respectively.

A control method suitable for intelligent phase electric output exchanger includes judging the switching failure of composite switchWhen the fault self-checking switch is used, the switching fault of the compound switch comprises a silicon controlled switch K_bNon-conductive fault, magnetic latching relay switch K_cFailure-to-close fault, magnetic latching relay switch K_cCan not break fault and silicon controlled switch K_bA fail-to-shut failure of (1); therefore, the process of judging the switching fault of the compound switch comprises the following steps:

(7-1) judging the silicon controlled switch K_bThe process for failing to conduct the fault is:

when the compound switch is put into use, the silicon controlled switch K is assumed_bIn an off state and magnetically holding relay switch K_cAlso under the precondition of being in the off state,

(7-1-1) the controller firstly sends the voltage to the silicon controlled switch K_bSending out a conduction control signal, and waiting for the thyristor switch K by the controller_bThe trigger pulse signal returned by the operation detection circuit is counted by using a pulse counter of the controller, and after the time delay is 0.2s, if the number of the trigger pulses received by the controller is more than 5, the silicon controlled switch K can be considered to be the silicon controlled switch K_bCan be normally conducted, if the number of the trigger pulses received by the controller is less than the set number,

(7-1-2) the controller sends the voltage to the thyristor switch K_bSending out a conduction control signal, resetting the pulse counter, delaying for 0.2s again, and judging the silicon controlled switch K if the number of trigger pulses received by the controller is still less than 5_bFailure to conduct the fault;

(7-2) judging magnetic latching relay switch K_cThe process for failing to close the fault is:

when the compound switch is put into use, the silicon controlled switch K is assumed_bCan be normally conducted, and the silicon controlled switch K_bHas been in a conducting state and magnetically holds the relay switch K_cOn the premise of being in the off state,

(7-2-1) first, the controller keeps the relay switch K to be magnetic_cSending out a closing control signal, resetting the pulse counter, delaying for 0.6s, and if the controller receives a silicon controlled switch K_bHas a large number of trigger pulsesIn the case of 20 of the above-mentioned two groups,

(7-2-2) magnetically holding the relay switch K by the controller_cSending out a disconnection control signal, resetting the pulse counter, delaying for 0.6s, and if the controller receives the silicon controlled switch K_bIs greater than 20 trigger pulses,

(7-2-3) again keeping the relay switch K magnetically by the controller_cSending out a closing control signal, resetting the pulse counter, delaying for 0.6s again, and if the controller receives the silicon controlled switch K_bWhen the number of trigger pulses is still more than 20, the magnetic latching relay switch K can be judged_cFailure to close the fault;

(7-3) judging magnetic latching relay switch K_cThe process for failing to disconnect the fault is:

when the compound switch is cut off, a silicon controlled switch K is assumed_bCan be normally conducted, and the silicon controlled switch K_bHas been in an off state and magnetically holds the relay switch K_cOn the premise that the valve is already in the closed state,

(7-3-1) the controller firstly sends the voltage to the silicon controlled switch K_bSending out a conduction control signal to let the silicon controlled switch K_bConducting and delaying the thyristor switch K by 0.4s_bReliably conducted and magnetically held by the controller to the relay switch K_cSending out a disconnection control signal, resetting the pulse counter, waiting for 0.6s, and if the controller receives the silicon controlled switch K_bWhen the number of trigger pulses is less than 20;

(7-3-2) magnetically holding the relay switch K by the controller_cSending out a disconnection control signal, resetting the pulse counter, waiting for 0.6s again, and if the controller receives the silicon controlled switch K_bWhen the number of the trigger pulses is less than 20, the magnetic latching relay switch K can be judged_cFailure to disconnect the fault;

(7-4) judging the silicon controlled switch K_bThe process for failing to shut down the fault is:

when the combination switch is cut off, a magnetic latching relay switch K is assumed_cCan be normally disconnected and magnetically holds the relay switch K_cHas been in an off state and has a thyristor switch K_bOn the premise of being still in the on state,

(7-4-1) the controller firstly sends the voltage to the silicon controlled switch K_bSending a turn-off control signal, resetting the pulse counter, delaying for 0.2s, and if the controller receives the silicon controlled switch K_bWhen the number of the trigger pulses is more than 5;

(7-4-2) then the controller sends the signal to the silicon controlled switch K_bSending a turn-off control signal, resetting the pulse counter, delaying for 0.2s again, and if the controller receives the silicon controlled switch K_bWhen the number of the trigger pulses is still more than 5, the silicon controlled switch K can be judged_bThe failure cannot be turned off.

A control method suitable for the electric output switching unit of intellectual phase, the compound switch also includes the timer connected with controller and sets up the software arc extinction module in the controller;

because the photoelectric coupler OPT has certain conduction voltage drop and transmission delay, the controller receives the current output signal U of the photoelectric coupler OPT_IOWith time delay, when the controller judges the current output signal U of the photoelectric coupler OPT_IOWhen the zero-crossing point is reached, the actual current may have reached other non-zero values, which generates a current output signal U that the controller judges to be the photocoupler OPT_IOLag time t at zero crossing₁；

Also because the magnetic latching relay switch K_cThe blade needs to overcome the pressure of the relay contact to pull the blade away from the relay contact, which results in a magnetically held relay switch K_cDelay time t of relay operation₂；

Taking into account the above objective existing lag time and delay time; each phase current of the three-phase power respectively forms a corresponding current waveform L in the three-phase power factor monitor;

when the current waveform L of a certain phase of three phases, namely an A phase, a B phase and a C phase, needs to be acquired, the controller starts a software arc extinction module to read the waveform zero crossing time t of the current waveform L of the corresponding phase in the three-phase power factor monitor₀And when the zero crossing point of the waveform is detectedTime t₀Starting a timer;

setting the period of a current waveform L as T and setting N as a positive integer; and if the time point of the closing command when the controller sends the closing control signal to the magnetic latching relay switch Kc is t, the controller will send a closing command to the magnetic latching relay switch

The time for completely switching on the magnetic latching relay switch Kc can be calculated according to t; because the magnetism keeps the relay switch K_cThe closing time and the breaking time are equal, so that the controller magnetically keeps the relay switch K_cThe time point of the release command when the release control signal is issued is also t.

Preferably, the controller starts the software arc extinction module to read the waveform zero-crossing time t of the current waveform L of the corresponding phase in the three-phase power factor monitor₀In time, the exact time point when the waveform just crosses zero is not easy to obtain; therefore, after reading the time points twice on the zero-crossing section waveform of the current waveform L, calculating the average value of the two time points as the waveform zero-crossing time t of the current waveform L₀A value of (d);

if the time points of two readings on the zero-crossing section waveform of the current waveform L are respectively t3 and t₄Then, then

Substituting equation (2) into equation (1) has

The invention can achieve the following effects:

the load interface power supply phase of the three-phase four-wire power supply can be easily changed, the load interface power supply phase can be automatically exchanged according to the unbalance of power factors in three phases, the safety is high, the reliability is good, the self switching fault of the compound switch can be intelligently and automatically detected, the switching of the compound switch can be carried out at the accurate time point of the current zero crossing point, and the intelligent degree is high. The flexibility of the load switching of the power grid can be enhanced, the reliability of the phase-to-phase power switching is also enhanced, and the stability and the reliability of the operation of the power grid can be greatly improved.

Drawings

Fig. 1 is a schematic diagram of a circuit principle connection structure when a power supply phase on a first load interface is supplied by an a phase, a power supply phase on a second load interface is supplied by a B phase, and a power supply phase on a third load interface is supplied by a C phase.

Fig. 2 is a schematic circuit schematic connection structure diagram when the sampling switch blade of the first phase voltage sampling circuit is connected to the a sampling end of the first phase voltage sampling circuit, the sampling switch blade of the second phase voltage sampling circuit is connected to the c sampling end of the second phase voltage sampling circuit, and the switch K1 and the switch K21 are closed.

Fig. 3 is a schematic diagram of a schematic circuit connection structure when the switch K4, the switch K9, the switch K18 and the switch K7 are closed on the basis of fig. 2.

Fig. 4 is a schematic diagram of a schematic circuit connection structure when the sampling blade of the first-phase voltage sampling circuit is connected to the c sampling terminal of the first-phase voltage sampling circuit and the sampling blade of the second-phase voltage sampling circuit is connected to the a sampling terminal of the second-phase voltage sampling circuit based on fig. 3.

Fig. 5 is a schematic circuit schematic connection structure diagram when the sampling blade of the first-phase voltage sampling circuit is connected to the d sampling end of the first-phase voltage sampling circuit, the sampling blade of the second-phase voltage sampling circuit is connected to the d sampling end of the second-phase voltage sampling circuit, the switch K10 is closed, the switch K4 is opened, the switch K13 is closed, and the switch K18 is opened on the basis of fig. 4.

Fig. 6 is a schematic diagram of a connection structure of a circuit principle after the switch K1 and the switch K21 are opened on the basis of fig. 4, so that the power supply phase on the first load interface is changed from a-phase power supply to C-phase power supply, and the power supply phase on the third load interface is changed from C-phase power supply to a-phase power supply.

Fig. 7 is a schematic diagram of a schematic circuit connection structure in which the power supply phase on the first load interface is supplied by the B phase and the power supply phase on the second load interface is supplied by the a phase.

Fig. 8 is a schematic diagram of a schematic circuit connection structure in which the power supply phase on the second load interface is supplied by the C phase and the power supply phase on the third load interface is supplied by the B phase.

Fig. 9 is a schematic view of a connection structure in which the conductive tube of the plug is not yet inserted and connected into the insulating tube.

Fig. 10 is a schematic view of a connection structure in which the conductive tube of the plug has been inserted and connected into the insulating tube.

Fig. 11 is a schematic diagram of a schematic circuit connection at the compound switch.

FIG. 12 shows a thyristor switch K_bA waveform schematic diagram of (1).

Fig. 13 is a schematic view of a current waveform for implementing switching on or off in a current reading manner.

Detailed Description

The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings.

Example 1: an intelligent phase electric output switching device, see fig. 1 and 11, including a phase a, a phase B, a phase C, a zero line N, A connection port, a phase B connection port, a phase C connection port, a first load interface 811, a second load interface 822, a third load interface 833, a controller 107, a node J1, a node J2, a node J3, a node J4, a node J5, a node J6, a node J7, and a node J8;

the system also comprises a three-phase power factor monitor 101, a first phase voltage sampling circuit 102, a first single-phase inverter power supply 103, a first filter 104, a first isolation transformer 105, a first load interface voltage sampling circuit 108, an interface power factor monitor 109, a second phase voltage sampling circuit 110, a second single-phase inverter power supply 1030, a second filter 1040, a second isolation transformer 1050, a second load interface voltage sampling circuit 1080, a switch K1, a switch K2, a switch K3, a switch K4, a switch K5, a switch K6, a switch K7, a switch K8, a switch K9, a switch K10, a switch K11, a switch K12, a switch K13, a switch K14, a switch K15, a switch K16, a switch K17, a switch K18, a switch K19, a switch K20 and a switch K21 which are respectively connected with the controller;

the compound switch comprises a first node 701, a second node 702, a first switch 2011, a second switch 2021, a third switch 2031, a fourth switch 2041, a fifth switch 2051, a sixth switch 2061 and a node M_aNode M_bNode M_cNode M_dNode M_eInductor L_aCapacitor C_aCapacitor C₀Capacitor C₂Diode D₁Diode D₂Diode D₃Diode D₄Photoelectric coupler OPT and resistor R₀Resistance R₁Resistance R₂And a change-over switch K_aMagnetic drive circuit 502, silicon drive circuit 503, self-powered power supply module 901 and groundAt terminal SGND, controller 107 includes pulse counter 805; change-over switch K_aComprising a thyristor switch K_bAnd magnetic latching relay switch K_cThe photo coupler OPT comprises a light emitting diode D₅And a photo transistor Q₀(ii) a Silicon controlled switch K_bAnd a magnetically held relay switch K_cOne end of the first and second switches is respectively connected with a first node, and the thyristor switch K_bThe other end of the first switch, one end of the third switch, one end of the fourth switch and the inductor L_aOne end of each is connected with the node M_aConnection, inductance L_aAnother terminal of (1), a capacitor C_aOne end of the first switch, one end of the second switch, one end of the fifth switch and one end of the sixth switch are respectively connected with the node M_bConnecting, magnetic latching relay switch K_cThe other end of the first switch and the other end of the second switch are respectively connected with a node M_cConnection, capacitance C₂One end of the fourth switch, the other end of the fourth switch and a diode D₁Positive terminal of (2) and diode D₃Respectively with the node M_dConnected, diode D₂Anode terminal of (1), diode D₄Negative terminal of (1), capacitor C₀And a resistor R₂One end of each is connected with the node M_eThe other end of the third switch is connected with one end of a resistor R1, and the other end of a resistor R1 is connected with a capacitor C₂The other end of the fifth switch is connected with a capacitor C₀The other end of the sixth switch is connected with a resistor R₂Is connected at the other end to a capacitor C_aThe other end of the diode D is connected to a second node₁And diode D₂Are respectively connected with the light emitting diode D₅On the positive terminal of a diode D₃Positive terminal of (2) and diode D₄Are respectively connected with the positive terminals of the light emitting diodes D₅On the negative terminal of the triode, a phototriode Q₀Respectively with the resistor R₀Is connected with a controller, a phototriode Q₀The emitter of the power supply module is connected with a signal grounding end SGND, and the self-powered power supply module is respectively connected with a resistor R₀Is connected with the other end of the magnetic driving circuit, the silicon driving circuit and the controller, and siliconThe drive circuit is respectively connected with a silicon controlled switch K_bIs connected with the controller, and the magnetic drive circuit is respectively connected with a magnetic latching relay switch K_cThe control end of the controller is connected with the controller;

in the same time section, the first node 701 can only be in conductive connection with one of the three phases of the phase A, the phase B and the phase C; node two 702 is connected to neutral line N.

When the device is used, the first node is connected to a live wire C of a power supply, and the second node is connected to a zero line N of the power supply.

In the composite switch of the scheme, the inductor L_aUsing high-frequency inductors, inductors L_aThe inductance of (a) is several tens of microhenries. When the thyristor switch K_bOr magnetic latching relay switch K_cAt the moment of conduction, the impedance of the capacitor Ca is about 0, and due to the inductor L_aPresence of an inductance L_aAt the moment of conduction, its frequency changes greatly, and the inductance L_aThe impedance of the power supply is also large, and the impact current at the moment of power supply conduction is restrained; when the circuit normally works, the inductor L is arranged because the power frequency is 50Hz power frequency_aIs very small.

At the inductor L_aMiddle and high inductance L_aVoltage U of_LaLeading inductance L_aCurrent of (I)₁90 degrees, i.e. inductance L_aCurrent of (I)₁Lagging inductance L_aVoltage U of_La90 degrees.

In the capacitor C₀Middle and high capacitance C₀Current of (I)₂Leading capacitor C₀Voltage U of_C090 degrees, i.e. capacitance C₀Voltage U of_C0Lagging capacitor C₀Current of (I)₂90 degrees.

Current I₁Through an inductance L_aThe capacitor Ca forms a closed loop and has an inductor L_aVoltage U on_LaLeading inductance L_aCurrent I of₁90 degrees.

When inductance L_aVoltage U of_LaNode M at a certain moment_aThe point is positive node M_bWhen the point is negative, the current I₂Slave node M_aPoint-pass diode D₁And a second light emitting elementPolar tube D₅Diode D₄And a capacitor C₀Forming a branch.

Neglecting diode D₁And a light emitting diode D₅And a diode D₄Is obviously of U_La＝U_C0I.e. the inductance L_aVoltage U of_LaIs equal to the capacitance C₀Voltage U of_C0. Obviously having an inductance L_aVoltage U on_LaHysteresis capacitance C₀Current I of₂90 degrees and thus a capacitance C₀Current I of₂And an inductance L_aCurrent I of₁In opposite directions, i.e. current I₂And current I₁Are opposite to each other. U shape_CNIs the voltage on the hot line C. For convenience of description, phase A, phase B and phase C are collectively referred to as "hot wire".

When current I₂Forward direction and larger than the light emitting diode D₅Output signal U of photoelectric coupler at minimum current of light emission_IONamely, the high level is changed into the low level, and the capacitor C is reasonably selected₀Make the capacitor C₀Current I of₂Forward zero crossing point and can reach the LED D quickly₅Minimum current to emit light.

When current I₂After positive zero crossing point, output signal U of photoelectric coupler_IOI.e. from high to low, due to the current I₂And current I₁In reverse, there is an output signal U of the photoelectric coupler_IOWhen changing from low level to high level, the current I₁Just at the positive zero crossing. The output signal U of the optocoupler is therefore_IOWhen changing from low level to high level, the current I is obtained₁The zero crossing point current of. When the current I is obtained₁When the zero crossing current is in zero, the controller can immediately supply the magnetic latching relay switch K_cAn open or close signal is issued. Keeping relay switch K magnetically if necessary_cWhen the relay is disconnected, the controller gives a magnetic latching relay switch K_cSends out a turn-off control signal to magnetically hold a relay switch K_cThen the circuit is disconnected; keeping relay switch K magnetically if necessary_cWhen the switch is closed, the controller gives a magnetic latching relay switch K_cSending out a closing control signal to magnetically hold a relay switch K_cThen close. Obtaining the accurate time point when the current passes through the zero crossing point, and then carrying out magnetic latching on the relay switch K according to the accurate time point_cSending out an open or close control signal to make the magnetic latching relay switch K_cIs opened or closed, while flowing through a magnetically held relay switch K_cIs small, opens or closes the magnetic latching relay switch K at low current_cMake the magnetic latching relay switch K_cThe contact of (2) is not easy to damage. Thereby effectively prolonging the magnetic latching relay switch K_cAnd the service life of the compound switch is further prolonged.

When the combination switch is put into use, because the silicon controlled switch K_bAt the moment of conduction, due to the inductance L_aThe current suppression effect of the thyristor does not generate large impact current, and the thyristor switch K_bHas a small conduction voltage drop and an inductance L_aImpedance is very small at power frequency, node M_aAnd node M_bThe voltage drop between the two points is small, and the magnetic latching relay switch K is closed at the moment_cTo magnetic latching relay switch K_cHas little damage to the contacts, thereby effectively prolonging the length of the silicon-controlled switch K_bAnd the service life of the compound switch is further prolonged.

At the thyristor switch K_bOn and magnetically holding relay switch K_cWhen closed, if the silicon controlled switch K is to be turned off_bAt a current I₁Let the thyristor switch K at zero crossing_bCut off, thus effectively protecting the silicon controlled switch K_bThe service life of (2).

Thyristor switches K for compound switching only when the line C is to be exposed to fire_bThe voltage is input when the voltage crosses zero, and the current zero crossing is adopted for input or cut-off as long as the composite switch has current, so that the service life of the composite switch is greatly prolonged, the reliability is high, and the safety is good.

When the thyristor switch K_bWhen conducting, the magnetic latching relay switch K_cMagnetic retention at the time of not yet disconnectedRelay switch K_cAlso conducting, i.e. thyristor switch K_bAnd magnetic latching relay switch K_cAt the same time in the on state. Because of the silicon controlled switch K_bThe branch circuit has an inductance L_aOn-resistance of, obviously magnetically holding, relay switch K_cThe impedance of the branch is far less than that of the thyristor switch K_bThe impedance of the branch thus flowing through the magnetically held relay switch K_cIs greater than the current flowing through the thyristor switch K_bThe current of the branch. If magnetic latching relay switch K_cThe contact is not opened at the current zero crossing point, and the contact is easily damaged. From the through-gain inductance L_aCurrent I of the branch₁At the accurate time point when the zero crossing point is reached, the controller sends out a control signal to disconnect the magnetic latching relay switch K_cContact of (1) making magnetic latching relay switch K_cWhen the current is small, the magnetic latching relay switch K is closed or opened, so that the magnetic latching relay switch K is not easy to burn out_cUpper contact effectively prolongs the magnetic latching relay switch K_cThe service life of the compound switch is further prolonged, the structure is simple, and the reliability is high.

A control method suitable for an intelligent phase electric output exchange device comprises the following steps:

the control method comprises a zero-crossing switching control process of the compound switch, and when the compound switch is used as a zero-crossing switching switch, the zero-crossing switching control process of the compound switch is as follows:

(4-1) putting a compound switch;

(4-2) cutting off the combination switch;

The control method also comprises a load interface power supply phase automatic exchange process, wherein the load interface power supply phase automatic exchange process comprises the following steps:

if the controller calculates and processes the monitoring data uploaded by the three-phase power factor monitor to obtain the phase with the maximum current power factor as the A phase, the phase with the minimum current power factor as the C phase and the active power factor P at the moment_ACGreater than a set value P₀When the load is connected with the first load interface, the second load interface and the third load interface, the first load interface, the second load interface and the third load interface are required to be determined;

as shown in fig. 1, if it is determined that the power supply phase on the first load interface is supplied by the a phase, the power supply phase on the second load interface is supplied by the B phase, and the power supply phase on the third load interface is supplied by the C phase, then the switches K7, K8, and K9 are all in the closed state, and the switches K1, K2, K3, K4, K5, K6, K10, K11, K12, K13, K14, K15, K16, K17, and K18 are all in the open state, and at this time, the sampling blade of the first-phase voltage sampling circuit is located at the d end, and the sampling blade of the second-phase voltage sampling circuit is located at the d end;

(5-4) Absolute value obtained by making difference between two absolute values of power factors on A phase, B phase and C phaseValue less than set value P₀If the power supply phase on the first load interface is changed from the phase A to the phase C, the power supply phase on the second load interface is still supplied from the phase B, and the power supply phase on the third load interface is changed from the phase C to the phase A;

(5-5-1) firstly, connecting a sampling knife switch of the first phase voltage sampling circuit to a sampling end a of the first phase voltage sampling circuit to be communicated with a phase A, and acquiring a voltage signal of the phase A and uploading the voltage signal to a controller by the first phase voltage sampling circuit as shown in figure 2;

then, a switch K1 is closed to enable the first single-phase inverter power supply to be connected with the phase A; referring to fig. 3, under the control of the controller, the voltage signal output by the first single-phase inverter power supply takes the voltage signal of the a phase as a reference, and the voltage signal output by the first single-phase inverter power supply as a feedback signal to form first closed-loop control, a first driving signal is generated in the controller, so that the first voltage waveform output by the first single-phase inverter power supply is filtered by a first filter and then is output by a first isolation transformer to form a stable first sine wave power supply, and the first sine wave power supply output by the first isolation transformer and the a phase voltage have the same amplitude and the same phase under the control of the controller;

then, the switch K4 and the switch K9 are closed at the same time, and the state of the power supply phase on the first load interface is the same as that of the power supply phase on the phase a;

then, the switch K1 is still closed, the sampling knife of the first phase voltage sampling circuit is connected to the C sampling end of the first phase voltage sampling circuit to be communicated with the C phase, and the first phase voltage sampling circuit collects the voltage signal of the C phase and uploads the voltage signal to the controller, as shown in fig. 4; the controller adopts phase shift control, so that a voltage signal output by a first single-phase inverter power supply takes a voltage signal of a C phase as a reference, and a voltage signal output by the first single-phase inverter power supply as a feedback signal to form new first closed-loop control;

(5-5-2) similarly, connecting a sampling knife switch of the second-phase voltage sampling circuit to a C sampling end of the second-phase voltage sampling circuit to be communicated with the C phase, and acquiring a C-phase voltage signal by the second-phase voltage sampling circuit and uploading the C-phase voltage signal to a controller, as shown in fig. 2;

then, a switch K21 is closed to enable the second single-phase inverter power supply to be connected with the C; referring to fig. 3, under the control of the controller, the voltage signal output by the second single-phase inverter power supply takes the voltage signal of the C phase as a reference, and the voltage signal output by the second single-phase inverter power supply as a feedback signal to form a second closed-loop control, and a second driving signal is generated in the controller, so that a second voltage waveform output by the second single-phase inverter power supply is filtered by a second filter and then is output by a second isolation transformer to a stable second sine wave power supply, and the second sine wave power supply output by the second isolation transformer and the voltage of the C phase have the same amplitude and the same phase under the control of the controller;

then, the switch K21 is still closed, and the sampling knife of the second-phase voltage sampling circuit is connected to the a sampling end of the second-phase voltage sampling circuit to be connected with the a phase, as shown in fig. 4, the second-phase voltage sampling circuit collects the voltage signal of the a phase and uploads the voltage signal to the controller; the controller adopts phase shift control to enable a voltage signal output by the second single-phase inverter power supply to take an A-phase voltage signal as a reference and take a voltage signal output by the second single-phase inverter power supply as a feedback signal to form new second closed-loop control, a second driving signal of SPWM is generated in the controller, a second voltage waveform output by the second single-phase inverter power supply is filtered by a second filter and then is output by a second isolation transformer to form a stable second sine wave power supply, the second sine wave power supply output by the second isolation transformer and the A-phase voltage have the same amplitude and the same phase under the control of the controller, and the state of a power supply phase on a third load interface is the same as the state of a power supply phase on the A-phase;

(5-5-3) then, closing the switch K10, opening the switch K4, closing the switch K13 and opening the switch K18 simultaneously, as shown in FIG. 5, wherein the power supply phase on the first load interface is completely supplied by the C phase, and the power supply phase on the third load interface is completely supplied by the A phase;

(5-5-4) finally, rotating the sampling knife switch of the first phase voltage sampling circuit to the d end, rotating the sampling knife switch of the second phase voltage sampling circuit to the d end, and disconnecting the switch K1 and the switch K21, as shown in fig. 6, so that the first phase voltage sampling circuit, the first single-phase inverter power supply, the first filter, the first isolation transformer, the second phase voltage sampling circuit, the second single-phase inverter power supply, the second filter and the second isolation transformer all exit the load interface to supply the automatic phase switching operation;

Referring to fig. 7, the power supply phase on the first load interface is supplied by phase B and the power supply phase on the second load interface is supplied by phase a.

Referring to fig. 8, the power supply phase on the second load interface is supplied by phase C and the power supply phase on the third load interface is supplied by phase B.

(III) the control method also comprisesWhen the compound switch is used as a fault self-checking switch, the self-switching fault of the compound switch comprises a silicon controlled switch K_bNon-conductive fault, magnetic latching relay switch K_cFailure-to-close fault, magnetic latching relay switch K_cCan not break fault and silicon controlled switch K_bA fail-to-shut failure of (1); therefore, the process of judging the switching fault of the compound switch comprises the following steps:

(7-2-1) first, the controller keeps the relay switch K to be magnetic_cSending out a closing control signal, resetting the pulse counter and delaying for 0.6sIf the controller receives the silicon controlled switch K_bIs greater than 20 trigger pulses,

when the combination switch is cut off, the magnetic latching relay is supposed to be openedOff K_cCan be normally disconnected and magnetically holds the relay switch K_cHas been in an off state and has a thyristor switch K_bOn the premise of being still in the on state,

The embodiment can enable the load interface power supply phase of the three-phase four-wire power supply to be easily changed, can automatically exchange the load interface power supply phase according to the unbalance of the power factors on the three phases, has high safety and good reliability, can intelligently and automatically detect the self switching fault of the compound switch, can also carry out the switching of the compound switch at the accurate time point of the current zero crossing point, and has high intelligent degree.

Example 2, the difference from example 1 is:

referring to fig. 1, 9 and 10, the first load interface 811 is a quick connection port, the quick connection port includes a plug 34 and a housing 39, an insulating tube 31 is fixed upward on the upper surface of the housing, a pressure sensor 32 connected to a controller is arranged on the outer wall of the insulating tube, a through hole communicated with an inner cavity 38 of the housing is fixed on the upper surface of the housing surrounded by the insulating tube, a pin 37 is fixed in the through hole, the lower end of the pin is located in the inner cavity of the housing, and the upper end of the pin is located in the insulating tube; two ends of a lead 30 are respectively connected with the lower end of the contact pin and the joint J6 in a conductive manner; the plug comprises an insulating insertion tube 36 and a conducting tube 35 arranged in the insulating insertion tube; the inner diameter of the insulating insertion tube is matched with the outer diameter of the insulating tube, and the diameter of the contact pin is matched with the inner diameter of the conductive tube; the structure of the second load interface 822 and the structure of the third load interface 833 are identical to the structure of the first load interface 811. A tapered tip 33 is provided at the tip of the pin.

Example 3, the difference from example 1 is:

referring to fig. 1 and 11, the system further includes a memory 106, a wireless module 504, an address encoder 507, and a server 200, which are respectively connected to the controller.

If the intelligent phase electric output switching devices are two, the two intelligent phase electric output switching devices can be in mutual wireless signal connection with each other through respective wireless modules;

Example 4, the difference from example 1 is:

referring to fig. 1, 11 and 13, the compound switch further includes a timer (not shown in the drawings) connected to the controller and a software arc suppression module (not shown in the drawings) disposed in the controller;

when the current waveform L of a certain phase of three phases, namely an A phase, a B phase and a C phase, needs to be acquired, the controller starts a software arc extinction module to read the waveform zero crossing time t of the current waveform L of the corresponding phase in the three-phase power factor monitor₀And at the time t when the zero crossing point of the waveform is detected₀Starting a timer;

Reading the waveform zero-crossing time t of the current waveform L of the corresponding phase in the three-phase power factor monitor by starting a software arc extinction module at the controller₀In time, the exact time point when the waveform just crosses zero is not easy to obtain; therefore, after reading the time points twice on the zero-crossing section waveform of the current waveform L, calculating the average value of the two time points as the waveform zero-crossing time t of the current waveform L₀A value of (d);

Substituting equation (2) into equation (1) has

The embodiment adopts software cooperation, and improves the reliability and the accuracy.

The embodiments of the present invention have been described above with reference to the accompanying drawings, but the implementation is not limited to the above-described embodiments, and those skilled in the art can make various changes or modifications within the scope of the appended claims.

Claims

1. The intelligent phase electric output switching device is characterized by comprising an A phase, a B phase, a C phase, a zero line N, A wiring port, a B wiring port, a C wiring port, a first load interface (811), a second load interface (822), a third load interface (833), a controller (107), a node J1, a node J2, a node J3, a node J4, a node J5, a node J6, a node J7 and a node J8;

the power factor monitoring device further comprises a three-phase power factor monitor (101), a first phase voltage sampling circuit (102), a first single-phase inverter power supply (103), a first filter (104), a first isolation transformer (105), a first load interface voltage sampling circuit (108), an interface power factor monitor (109), a second phase voltage sampling circuit (110), a second single-phase inverter power supply (1030), a second filter (1040), a second isolation transformer (1050), a second load interface voltage sampling circuit (1080), a switch K1, a switch K2, a switch K3, a switch K4, a switch K5, a switch K6, a switch K7, a switch K8, a switch K9, a switch K10, a switch K11, a switch K12, a switch K13, a switch K14, a switch K15, a switch K16, a switch K17, a switch K18, a switch K19, a switch K20 and a switch K21 which are respectively connected with the controller;

the power supply output end of the second isolation transformer, the sampling end of the second load interface voltage sampling circuit, one end of the switch K16, one end of the switch K17 and one end of the switch K18 are respectively connected with a node J5;

the other end of the switch K1, the other end of the switch K2 and the other end of the switch K3 are all connected with the power supply input end of a first single-phase inverter power supply, the input end of the first filter is connected with the power supply output end of the first single-phase inverter power supply, and the output end of the first filter is connected with the power supply input end of the first isolation transformer;

the compound switch comprises a first node (701), a second node (702), a first switch (2011), a second switch (2021), a third switch (2031), a fourth switch (2041), a fifth switch (2051), a sixth switch (2061) and a node M_aNode M_bNode M_cNode M_dNode M_eInductor L_aCapacitor C_aCapacitor C₀Capacitor C₂Diode D₁Diode D₂Diode D₃Diode D₄Photoelectric coupler OPT and resistor R₀Resistance R₁Resistance R₂And a change-over switch K_aThe controller comprises a magnetic driving circuit (502), a silicon driving circuit (503), a self-powered power supply module (901) and a grounding end SGND, wherein the controller (107) comprises a pulse counter (805); the change-over switch K_aComprising a thyristor switch K_bAnd magnetic latching relay switch K_cThe photoelectric coupler OPT comprises a light emitting diode D₅And a photo transistor Q₀(ii) a The silicon controlled switch K_bAnd a magnetically held relay switch K_cOne end of the silicon controlled switch K is respectively connected with a first node_bThe other end of the first switchOne end of a third switch, one end of a fourth switch and an inductor L_aOne end of each is connected with the node M_aConnection of said inductance L_aAnother terminal of (1), a capacitor C_aOne end of the first switch, one end of the second switch, one end of the fifth switch and one end of the sixth switch are respectively connected with the node M_bConnecting, magnetic latching relay switch K_cThe other end of the first switch and the other end of the second switch are respectively connected with a node M_cConnected, the capacitor C₂One end of the fourth switch, the other end of the fourth switch and a diode D₁Positive terminal of (2) and diode D₃Respectively with the node M_dConnected, the diode D₂Anode terminal of (1), diode D₄Negative terminal of (1), capacitor C₀And a resistor R₂One end of each is connected with the node M_eThe other end of the third switch is connected with one end of a resistor R1, and the other end of the resistor R1 is connected with a capacitor C₂The other end of the fifth switch is connected with a capacitor C₀The other end of the sixth switch is connected with a resistor R₂Is connected to the other end of the capacitor C_aThe other end of the diode D is connected to a second node₁And diode D₂Are respectively connected with the light emitting diode D₅On the positive terminal of the diode D₃Positive terminal of (2) and diode D₄Are respectively connected with the positive terminals of the light emitting diodes D₅On the negative terminal of said phototransistor Q₀Respectively with the resistor R₀Is connected with a controller, the phototriode Q₀Is connected with a signal grounding terminal SGND, and the self-powered power supply module is respectively connected with a resistor R₀The other end of the silicon-based switch, the magnetic driving circuit, the silicon driving circuit and the controller are connected, and the silicon driving circuit is respectively connected with the silicon controlled switch K_bThe magnetic drive circuit is respectively connected with a magnetic latching relay switch K_cThe control end of the controller is connected with the controller;

the first node (701) can be in conductive connection with only one of three phases, namely an A phase, a B phase and a C phase in the same time section; and the second node (702) is connected to a zero line N.

2. The intelligent phase-to-electricity output exchange device according to claim 1, wherein the first load interface (811) is a quick connector, the quick connector comprises a plug (34) and a shell (39), an insulating tube (31) is fixedly arranged on the upper surface of the shell upwards, a pressure sensor (32) connected with a controller is arranged on the outer wall of the insulating tube, a through hole communicated with an inner cavity (38) of the shell is fixedly arranged on the upper surface of the shell surrounded by the insulating tube, a contact pin (37) is fixedly arranged in the through hole, the lower end of the contact pin is positioned in the inner cavity of the shell, and the upper end of the contact pin is positioned in the insulating tube; two ends of a lead (30) are respectively connected with the lower end of the contact pin and the joint J6 in a conductive manner; the plug comprises an insulating insertion tube (36) and a conductive tube (35) arranged in the insulating insertion tube; the inner diameter of the insulating insertion tube is matched with the outer diameter of the insulating tube, and the diameter of the contact pin is matched with the inner diameter of the conductive tube; the structure of the second load interface (822) and the structure of the third load interface (833) are completely the same as the structure of the first load interface (811); the top end of the pin is provided with a conical tip (33).

3. A smart phase electrical output switching apparatus as claimed in claim 1 further comprising a memory (106), a wireless module (504), an address encoder (507) and a server (200) each connected to the controller.

4. A control method suitable for use in the intelligent phase electrical output switching apparatus of claim 1, the control method comprising a load interface power phase auto-switching process, the load interface power phase auto-switching process comprising:

(5-4) making the absolute value of the difference between the absolute values of the power factors on the A phase, the B phase and the C phase smaller thanSet value P₀If the power supply phase on the first load interface is changed from the phase A to the phase C, the power supply phase on the second load interface is still supplied from the phase B, and the power supply phase on the third load interface is changed from the phase C to the phase A;

5. A control method applied to the intelligent phase electric output switching device according to claim 3, wherein if there are two intelligent phase electric output switching devices, the two intelligent phase electric output switching devices are capable of performing mutual wireless signal connection of the two intelligent phase electric output switching devices through respective wireless modules;

6. A control method suitable for use in the intelligent phase electrical output switching apparatus of claim 1 wherein the compound switch further comprises a timer connected to the controller and a software arc suppression module disposed within the controller;

7. A control method suitable for the intelligent phase electric output exchange device as claimed in claim 6, wherein the controller starts the software arc extinction module to read the waveform zero-crossing time t of the current waveform L of the corresponding phase in the three-phase power factor monitor₀In time, the exact time point when the waveform just crosses zero is not easy to obtain; therefore, after reading the time points twice on the zero-crossing section waveform of the current waveform L, calculating the average value of the two time points as the waveform zero-crossing time t of the current waveform L₀A value of (d);

Substituting equation (2) into equation (1) has